"Horrible, isn't it? I suppose that's what the last remnants of the Lunarians have come to. Evidently once men and women, something like ourselves. I daresay the ancestors of that thing have lived here in coldness and darkness for hundreds of generations. It shows how tremendously tenacious Nature is of life."

―Lord Redgrave

The Lunarians are large humanoid creatures indigenous to Luna, the Earth's moon. They evolved from human-like surface dwellers, but were forced to migrate underground due to the moon slowly losing its atmosphere and water. Deep underneath Crater Newton, the last members of the race survive in a frigid but still inhabitable environment, the only place in the moon where oxygen and liquid water are still to be found. While the original race was civilized, building towns and temples on the surface; their subterranean descendants appear to have degenerated and live very much like wild animals.

They're described as vaguely ape-like, although with smooth hairless skin which is light grey in color. Unlike an ape, though, their lower limbs are more powerful than their upper limbs and their heads are described as big, round and smooth. Their skeletal structure is similar to a human's, with the notable distinction that the chest cavity is disproportionally expanded, containing enlarged lungs to enable them to breathe in a rarefied atmosphere.

The nose is described as long and thick, with huge mobile nostrils, and the mouth is vaguely fish-like and seemingly toothless. Also notable is that they no longer possess eyes, due to having adapted to a perpetually dark environment. Instead of fingernails, their fingers are equipped with long white feelers which they can extend and wave to sense the environment in search of water.

It's speculated that the species is cold-blooded, due to how they will dive into the frigid stream waters naturally and showing no discomfort. They feed on eel-like fish which they capture with their mouths during these dives. The Lunarians themselves risk falling prey to a large aquatic predator.